This invention relates to the production of electromagnets, and particularly substantially cylindrical superconductive magnets for use, for example, in magnetic resonance imaging (MRI) systems.
Typically, superconductive magnets for MRI systems are produced by winding superconductive wire onto a forming tool which is accurately machined with grooves to provide precise positioning for the wire. The wound coils may further be vacuum impregnated with resin to create a rigid structure.
Alternatively, a wet winding process may be used, in which a resin coated wire is used for coil winding onto the forming tool and the resulting coil structure is cured with heat.
In some cases, where the coils are subjected to strong forces during operation, it is necessary for the forming tool to remain in place to provide structural support for the coils. This is not always the case however and, in many circumstances, the resin impregnated coil structure is sufficiently self-supporting that the accurately machined forming tool can be removed for re-use.
In either event, however, difficulties arise in connection with high volume manufacture of superconductive magnets, in that each forming tool remains associated with a single coil set either permanently or at least for a significant time, extending from the set-up of the winding phase to the final setting of the resin. Thus, if magnets are to be produced at rates conducive to high volume production, many accurately machined forming tools are required. These are costly and demanding requirements.
One object of the invention is to provide a method of manufacturing a former which reduces the above described difficulties.